In the roofing industry and particularly the commercial roofing industry, exposed roofing membranes have become prevalent. Single ply roofing systems, and others using an exposed membrane, although very effective are subject to greater damage from hail impact than some other types of roof systems. One significant exacerbator of the potential for damage from hail is the very fasteners that retain the membrane and roof assembly component materials underlying the membrane. Such fasteners are nails, special clips, anchors or screws and typically have washers positioned thereunder to spread the hold down load of the head of the fastener. Because fasteners are generally immovable, connected to structural subjacent roof support materials or otherwise substantially immoveable, they pose particular risks to the overlying waterproofing membrane when hail strikes. The fastener/washer act essentially as an anvil against which the roofing membrane can be suddenly and violently compressed by the substantial momentum transfer from a hail stone. This compression tends to rapidly and for short duration “flow” the membrane material in all directions from the impact site. Rupture of the overlying waterproofing membrane can easily occur when hail hits the membrane in an area of an underlying fastener. In order to improve the hail resistance of such roof structures, this characteristic must be alleviated. The roofing industry tests for hail presently utilize a ½″ to 2″ steel ball. The ball is accelerated to terminal (free full) velocity and directed at a roof assembly to measure hail impact. Recently, hail testing has been developed further to enable the shooting of actual ice balls from an air cannon through a timing device at a roof assembly which has been cooled to 38° F. with chilled water. This test more realistically shows the effects of various size hail ice balls from ½″ to 5″ diameter at various mph speeds into a roof assembly sample. A 3″ hail ball approximately the size of a baseball will fall in still air at 95 to 97 mph. If the 3″ hail is caught in a down draft of wind it can increase its speed. Some 3″ hail impact dents on sheet metal equipment on roofs hit by hail required a 3″ hail ball to be shot at 150 mph to replicate the dent. At 100 mph, a 3″ hail ball will go through ½ inch APA approved oriented strand board (osb) wafer board and at 135 mph and a 3″ hail ball will go through ½″ plywood.